1. Field
One or more embodiments described herein relate to a display device and a method of driving a display device.
2. Description of the Related Art
A flat panel display (FPD) has a plurality of pixels for displaying images. Each pixel may include a red subpixel, a green subpixel, and a blue subpixel. Each of the subpixels are controlled based on data from an external source. The pixels may be arranged in various ways, such as a stripe structure, a mosaic structure, or a delta structure. In a mosaic structure, red, green, and blue subpixels are sequentially arranged in column and row directions. In a delta structure, pixels are alternately arranged in a zigzag pattern in the column direction, and red, green and blue subpixels are sequentially arranged.
One type of pixel arrangement having a PenTile structure may better express high resolution and, at the same time, may have reduced design cost. In a PenTile structure, red subpixels and blue subpixels are alternately formed in the same column, and green subpixels are formed in an adjacent column. The PenTile matrix structure reduces the numbers of red subpixels and blue subpixels by half, compared with the stripe structure. Accordingly, the total number of pixels is reduced to 2/3 compared with the stripe structure. This may result in a higher aperture ratio. In addition, the same perceived resolution as the stripe structure may be obtained through rendering driving.
Research has determined that blue light emitted from a display panel reduces the amount of melatonin produced in the human body. Melatonin is a hormone involved in biorhythms such as circadian and circannual rhythms by sensing a change in photoperiod, such as a change in sunshine duration according to the length of night or day or a seasonal change in sunshine duration. If a person is exposed to a large amount of blue light at night, his or her biorhythm may be broken, causing problems (such as meal time, perception of night and day and sleeping hours) with his or her body.
In attempt to solve these side effects, blue light (i.e., a unit color) of a display device may be divided into first blue light which is relatively highly efficient and second blue light which is relatively less efficient. Then, the first blue light may be used in the daytime, and the second blue light may be used at night. Since the blue light used varies according to the time of the day when the display device is used, the effect of blue light on the human body may be reduced.
However, the number of pixels being driven is limited in a single driving mode (in which any one of the first blue light or the second blue light is driven) compared with a mixed driving mode (in which both the first blue light and the second blue light are driven). Therefore, the single driving mode reduces resolution, thus degrading display quality.